Just after 9:30 a.m. Sunday morning, two cars collided with a Muni bus at 24th and Guerrero streets; four people were injured, and all were taken to a nearby hospital with non-life-threatening injuries.

The cause of the incident remains unclear, and the crash occurred in a part of San Francisco where today's Bay to Breakers-spurred road closures — that created conditions rife for aggressively driven cars to collide with other vehicles — weren't put in place.

What is known, however, is at least four people were injured, according to NBC Bay Area. It's unclear what passengers from what vehicles sustained the injuries.

SFPD officers were on-site at the Mission District intersection for some time after the crash. No arrests have been made in relation to the collision, thus far.

Anyone with information is asked to contact the police department at (415) 575-4444.

Related: SF Muni Operator Dies After Falling 'Severely Ill' While Driving, Crashes into Parked Cars on Noe Street [2020]

Photo: Side view of hybrid electric San Francisco Municipal Railroad (MUNI) public transit bus in the Mission Bay neighborhood of San Francisco, California, June 18, 2019. (Photo by Smith Collection/Gado/Getty Images)